/* roulang page: index */
:root {
      --primary-dark: #0B3D3A;
      --primary-mid: #1A6B5A;
      --primary-light: #0F7BA0;
      --accent-amber: #F5A623;
      --bg-light: #F7F9FC;
      --text-title: #1A2A36;
      --text-body: #3E4C59;
      --text-muted: #7B8794;
      --success-green: #2D9C6B;
      --gradient-main: linear-gradient(135deg, #0B3D3A 0%, #1A6B5A 40%, #0F7BA0 100%);
      --card-shadow: 0 4px 20px rgba(0,0,0,0.04), 0 1px 3px rgba(0,0,0,0.06);
      --card-shadow-hover: 0 12px 30px rgba(0,0,0,0.08), 0 4px 8px rgba(0,0,0,0.1);
      --radius-card: 16px;
      --radius-btn: 50px;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", system-ui, -apple-system, sans-serif;
    }
    * {
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--bg-light);
      color: var(--text-body);
      line-height: 1.7;
      margin: 0;
      padding-top: 80px;
    }
    h1, h2, h3, h4, .h1, .h2, .h3 {
      color: var(--text-title);
      font-weight: 700;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: all 0.2s ease;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    .section-padding {
      padding: 100px 0;
    }
    @media (max-width: 768px) {
      .section-padding {
        padding: 60px 0;
      }
      body {
        padding-top: 70px;
      }
    }

    /* 导航栏 */
    .navbar-custom {
      background: rgba(255,255,255,0.85);
      backdrop-filter: blur(12px);
      box-shadow: 0 2px 20px rgba(0,0,0,0.04);
      padding: 12px 0;
      transition: all 0.3s ease;
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
    }
    .navbar-scrolled {
      background: rgba(255,255,255,0.98);
      box-shadow: 0 4px 25px rgba(0,0,0,0.08);
    }
    .navbar-brand {
      font-size: 1.8rem;
      font-weight: 700;
      background: var(--gradient-main);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      display: flex;
      align-items: center;
      gap: 6px;
      letter-spacing: 1px;
    }
    .navbar-brand i {
      background: none;
      -webkit-text-fill-color: var(--accent-amber);
      font-size: 2rem;
    }
    .nav-link {
      color: var(--text-body) !important;
      font-weight: 500;
      margin: 0 12px;
      position: relative;
      padding: 6px 0 !important;
      font-size: 1rem;
    }
    .nav-link:hover, .nav-link.active {
      color: var(--primary-mid) !important;
    }
    .nav-link.active::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 100%;
      height: 3px;
      background: var(--gradient-main);
      border-radius: 3px;
    }
    .btn-outline-green {
      border: 2px solid var(--primary-mid);
      color: var(--primary-mid);
      background: transparent;
      border-radius: var(--radius-btn);
      padding: 8px 22px;
      font-weight: 600;
      transition: 0.25s;
    }
    .btn-outline-green:hover {
      background: rgba(26,107,90,0.1);
      color: var(--primary-mid);
    }
    .btn-primary-gradient {
      background: var(--gradient-main);
      border: none;
      color: white;
      border-radius: var(--radius-btn);
      padding: 10px 24px;
      font-weight: 600;
      box-shadow: 0 8px 18px rgba(11,61,58,0.25);
      transition: 0.25s;
    }
    .btn-primary-gradient:hover {
      filter: brightness(1.1);
      box-shadow: 0 12px 24px rgba(11,61,58,0.35);
      color: white;
    }
    .navbar-toggler {
      border: none;
      color: var(--text-title);
    }
    @media (max-width: 992px) {
      .navbar-collapse {
        background: white;
        padding: 20px;
        border-radius: 20px;
        margin-top: 15px;
        box-shadow: var(--card-shadow);
      }
    }

    /* Hero */
    .hero-section {
      background: linear-gradient(135deg, rgba(11,61,58,0.03) 0%, rgba(15,123,160,0.05) 100%);
      position: relative;
      overflow: hidden;
    }
    .hero-bg-geo {
      position: absolute;
      top: -40px;
      right: -20px;
      width: 50%;
      height: 120%;
      background: radial-gradient(circle at 30% 40%, rgba(26,107,90,0.08) 0%, transparent 60%);
      transform: rotate(5deg);
    }
    .hero-title {
      font-size: 3rem;
      font-weight: 700;
      line-height: 1.2;
      background: var(--gradient-main);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }
    .hero-badge {
      background: white;
      border-radius: 40px;
      padding: 8px 20px;
      box-shadow: 0 8px 18px rgba(0,0,0,0.04);
      display: inline-flex;
      align-items: center;
      gap: 12px;
      margin-right: 15px;
    }
    .badge-number {
      font-size: 2rem;
      font-weight: 800;
      color: var(--accent-amber);
      line-height: 1;
    }
    .badge-label {
      font-size: 0.9rem;
      color: var(--text-muted);
    }
    @media (max-width: 768px) {
      .hero-title {
        font-size: 2.2rem;
      }
      .hero-badge {
        margin-bottom: 12px;
      }
    }

    /* 板块标题 */
    .section-title {
      font-size: 2.2rem;
      font-weight: 700;
      margin-bottom: 16px;
      position: relative;
      display: inline-block;
    }
    .section-title::after {
      content: '';
      position: absolute;
      left: 0;
      bottom: -8px;
      width: 60px;
      height: 4px;
      background: var(--gradient-main);
      border-radius: 4px;
    }
    .text-accent {
      color: var(--accent-amber);
    }

    /* 卡片 */
    .advantage-card {
      background: white;
      border-radius: var(--radius-card);
      padding: 28px 24px;
      box-shadow: var(--card-shadow);
      transition: all 0.25s ease;
      border-left: 4px solid var(--primary-mid);
      height: 100%;
    }
    .advantage-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--card-shadow-hover);
    }
    .icon-circle {
      width: 64px;
      height: 64px;
      background: rgba(26,107,90,0.1);
      border-radius: 20px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 2rem;
      color: var(--primary-mid);
      margin-bottom: 20px;
    }
    .product-img {
      border-radius: 20px;
      box-shadow: 0 15px 30px rgba(0,0,0,0.08);
    }
    .scene-card {
      background: white;
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--card-shadow);
      transition: 0.25s;
    }
    .scene-card:hover {
      transform: translateY(-5px);
      box-shadow: var(--card-shadow-hover);
    }
    .scene-card img {
      transition: transform 0.4s ease;
    }
    .scene-card:hover img {
      transform: scale(1.03);
    }
    .data-badge {
      background: var(--gradient-main);
      color: white;
      border-radius: 30px;
      padding: 6px 18px;
      font-weight: 700;
      display: inline-block;
      margin-top: 10px;
    }
    .faq-accordion .accordion-button {
      background: #F0F4F8;
      border-radius: 10px;
      font-weight: 600;
      color: var(--text-title);
      box-shadow: none;
    }
    .faq-accordion .accordion-button:not(.collapsed) {
      background: var(--primary-mid);
      color: white;
    }
    .cta-banner {
      background: var(--gradient-main);
      border-radius: 30px;
      padding: 60px 40px;
      position: relative;
      overflow: hidden;
    }
    .footer-dark {
      background: #0B2A28;
      color: #B0C4C1;
    }
    .footer-dark a {
      color: #B0C4C1;
    }
    .footer-dark a:hover {
      color: white;
    }